Public Health England announced that 156 people had fallen ill including 55 cases in Hampshire, 33 in Cheshire and 43 in the West Midlands

An urgent investigation has been launched into a national outbreak of salmonella

Three people who were contracted Salmonella at a Birmingham Hospital have died.

But bosses at Birmingham's Heartlands Hospital have stressed at least two of the deaths are unrelated to the infection, while the third is still being investigated.

Public Health England today announced that 156 people had fallen ill including 55 cases in Hampshire, 33 in Cheshire and 43 in the West Midlands.

Of the 43 cases, 34 were connected to the Birmingham hospital.

A spokesman told ITV News: "One of the deaths is subject to a coroner’s inquest and therefore we are unable to comment at this stage.

"We can confirm that we have tested both food and water at the Heartlands site and have ruled these out as the root cause of the infection.

"We are working with the Public Health England to investigate the other two cases, which includes the possibility of the infection being community acquired."

Health officials have launched an urgent investigation into a national outbreak of Salmonella after more than 150 people across the country fell ill.

All the cases were originally viewed by experts as individual clusters. But in a dramatic development, public health officials are now investigating the possibility that they are all linked.

Testing using genetic typing methods has revealed that all of the 156 cases are infected with closely related strains. Experts say this suggests the cause of the illness is from a single source.

Dr Paul Cleary, a consultant epidemiologist who is charge of the national investigation, said: “We are working with our colleagues across PHE, at the Food Standards Agency, in local authorities and with other public health organisations in Europe to investigate the cause of this outbreak.

“We are making good progress and hope to have more conclusive evidence shortly.

“We will continue to monitor the situation and if there is any further public health action necessary then we will ensure that this takes place.”

Salmonella Enteritidis is a strain of bacteria that causes gastrointestinal illness and is often associated with poultry or eggs.

Common symptoms include diarrhoea, stomach cramps and sometimes vomiting and fever. Symptoms are self-limiting and most people recover without treatment but experts stress it is important to remain hydrated.